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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 0 |
| 7 | 0 |
| 8 | 0 |
| 9 | 0 |
| 10 | 0 |
| 11 | 0 |
| 12 | 0 |
| 13 | 0 |
| 14 | 1 |
| 15 | 1 |
| 16 | 0 |
| 17 | 10 |
| 18 | 20 |
| 19 | 45 |
| 20 | 44 |
| 21 | 265 |
| 22 | 1920 |
| 23 | 6300 |
| 24 | 13720 |
| 25 | 20175 |
| 26 | 18000 |
| 27 | 7570 |
| 28 | 357435 |
| 29 | 2398900 |
| 30 | 7499940 |
| 31 | 14372820 |
| 32 | 18433415 |
| 33 | 15729000 |
| 34 | 8171730 |
| 35 | 1975560 |
| 36 | 749649145 |
| 37 | 4695264000 |
| 38 | 13718863480 |
| 39 | 24545693760 |
| 40 | 29544855480 |
| 41 | 24545693760 |
| 42 | 13718863480 |
| 43 | 4695264000 |
| 44 | 749649145 |
[1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,0,10,20,45,44, 265,1920,6300,13720,20175,18000,7570,357435, 2398900,7499940,14372820,18433415,15729000, 8171730,1975560,749649145,4695264000,13718863480, 24545693760,29544855480,24545693760,13718863480, 4695264000,749649145] |